An Introduction to Access Servers

There are a variety of routers and gateways capable of voice/VOIP and dialup processing, as well as fax, video and other media. Some models are dialup-only, others VOIP-only, some as either a dialup unit or a VOIP unit (but all ports one or the other), while newer models are universal port models - any type of traffic on any port.

Access servers developed with the explosion of the internet in the mid 1990s, and the products of several companies came to dominate the market. These included Cisco's AS5200 and AS5300 (the AS5300 also has a newer, VOIP-only version), USR's Total Control Hub (later the Total Control 1000, when acquired by 3Com), Livingston's (later Lucent's) Portmaster series, and Lucents Max lines, including the Max 4000, 6000, and TNT (which also had later VOIP versions).

By 2000 VOIP and other types of traffic began to appear, and voice/video capable models emerged. These included the Cisco AS5350 and AS5400 (including their zoomed up HPX and XM versions) along with the AS5850, a high-density telco product, while Lucent added voice capabilities to its Max line, and a variety of smaller companies developed niche products, including most successfully in the 'softswitch' IP-to-IP market (addressed by Cisco by adding softswitch capabilities to its AS5 series products), and in broadband modem/DSL servers (like Lucent's Stinger and Zhone's DSLAM).

By 2005 Cisco had emerged as the dominant player in terms of voice/data/fax/video access servers. Cisco's products are the most widely deployed, with the widest selection of features, and the best overall feature set. These features include sophisticated and extensive IVR (voice prompt handling) support. In addition, Cisco implementations often become defacto standards. It is hard to go wrong choosing a Cisco VOIP router or gateway, and their widespread deployment make finding technical support relatively easier. However, there are alternatives that offer better prices or different feature sets, particularly with respect to dialup servers, that may make nonCisco products attractive. Pay attention to what the various models will and will not do - don't assume they'll do something not stated.

Use the table below as a quick guide to the various types of VOIP and dialup gateways available, then do more investigation to make sure which model is right for you. Continue reading »